This invention relates to an exhaust line for a cylinder bank of an internal combustion engine, an exhaust conveying duct being enclosed, beyond an air gap, by a housing at least partly surrounding the exhaust conveying duct, through which housing there is a flow of coolant.
Such an exhaust line is shown in German patent documents DE 42 06 247 issued Jun. 3, 1993 on an exhaust gas line for a row of cylinders of an internal combustion engine. This exhaust line has an extrusion-molded part made of light metal into which there are recessed several longitudinal chambers, mutually connected at least in the closure covers, for cooling water. This extrusion-molded part is approximately round in shape and has openings that are arranged in the region of the individual exhaust ports of the respective cylinder heads. Inserted into the extrusion-molded part is a one-piece gas conveying duct, which must be connected to the previously mentioned openings in gas-tight fashion, in a manner not described. Precise making of a connection is very costly. Inspection of the gas conveying duct after assembly is scarcely possible.
It is an object of the invention to furnish an exhaust line of easily maintainable construction for a cylinder bank of an internal combustion engine.
This object is achieved by virtue of the fact that the housing is split along the cylinder bank and has a housing base, into which the exhaust conveying duct is insertable, and a housing cover covering the housing base. A modular exhaust line construction is thereby created, which permits, for example, inspection of, in particular, the exhaust conveying duct at any time, without great effort, by removing the housing cover. In this way the air gap can be inspected over the entire length of the removed housing cover and examined, for example, for leaks of any kind that may be present.
In development of the invention, the housing base is divided into housing base segments, preferably U-shaped and enclosing a certain number of cylinders. These can be, for example, two cylinders each, so that identical housing base segments can be mounted for various internal combustion engines if, for example, the internal combustion engine is made as an eight- or 16-cylinder internal combustion engine of V design. Naturally, it is also contemplated in the context of the invention to provide additional housing base segments for, for example, three cylinders, so that other cylinder numbers are also feasible. In addition to these housing base segments, which are assigned to the individual cylinders, there are also various housing base end segments, which can be made, for example, as covers and/or connecting devices for a (liquid-cooled) turbocharger, with the incorporation of wastegate ducts if appropriate.
In corresponding development of the invention, the housing cover is likewise divided into housing cover segments enclosing a number of cylinders. What was said about the housing base segments applies as appropriate to these housing cover segments.
In development of the invention, the housing base segments are attachable to the cylinder heads and have openings in the region of the exhaust port of each cylinder head. In further development, the exhaust conveying duct is attachable to the individual cylinder heads in gas-tight fashion with flange regions extending into the openings. Thus, according to this design, the housing base segments are first mounted and then the exhaust conveying duct is inserted into these U-shaped housing base segments. Finally, the housing cover segments are then mounted. In particular, moreover, individual mounting or in particular removal, for example for the repairing of a cylinder, can take place by virtue of the fact that, in development of the invention, the exhaust conveying duct is formed by separate pipe segments assigned to each cylinder. Naturally, it is a prerequisite here that the cylinders or in particular the cylinder heads be removable individually or in correspondence to the segments of the housing base segments.
In development of the invention, the housing base segments have through coolant conveying ducts in the region of the two parallel arms of the U-shaped housing. Coolant, in particular cooling water, flows through these coolant conveying ducts in common. The coolant flows in one direction along the cylinder bank in both coolant conveying ducts. Accordingly, the housing base end segments are designed so that external or internal coolant ports are connectable to them and these coolant ports distribute the coolant into the coolant conveying ducts. These coolant conveying ducts are included in the coolant conveyance from the internal combustion engine discharge via the turbo charger to a plate head exchanger.
In further development of the invention, a coolant duct is also recessed in the housing cover. This coolant duct connects, along one cylinder bank A, a thermostat housing to an intercooler and, along the other cylinder bank B, the intercooler to the plate heat exchanger. These connections were formerly effected via separate pipes to be attached externally to the internal combustion engine. Integration of these lines into the housing cover results in, on the one hand, additional cooling of the exhaust pipe and, on the other, the saving of the formerly required pipes. Naturally, the corresponding ports, pipe clamps and hose connections are likewise saved.